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(Nb-Model.)-

G. B. SNOW. TIME MECHANISM FOR OPERATING GAS COCKS.

No. 507,564. Patented Oct. 31, 1893.

WiTNESSES= INVENTOR.

STATES PATENT Fries.

TIME MECHANISM l-OR OPERATING GAS-COCKS.

J SPECIFICATION forming part of Letters Patent No. 507,564, datedOctober 31, 1893.

Application filed September 21, 1892. Serial No. 446,393. (No model.)

To all whom it may concern.-

Be it known that I, GEORGE B. SNOW, a citizen of the United States,residing at Buffalo, in the county of Erie and State of New York, haveinvented certain Improvements in Tim ing Mechanism for Gas-Burners, ofwhich the following is aspecification.

My invention relates to mechanism for cutting off the gas supply from agas burner at a predetermined time. Its object is, the production of adevice for the purpose which can be cheaply made, and at the same timebe durable, easily operated, certain and effective. I attain theseobjects by means of the mechanism illustrated in the accompanyingdrawings, in which Figure 1. is a view of the device, showing the valvecasing in vertical section. Fig. 2. is a similar vertical section of thevalve casing, showing an alternative construction. Fig. 3. is a sideView of the casting-off screw, which is attached to the center arbor ofthe clock.

a represents a valve casing, attached by a flange o to a casing p, whichcontains an ordinary clock movement. The casing a contains a longstemmed valve 0 0; the

stem of which passes through a central hole in the screw-cap b, whichcloses the casing a, and forms a gas tight joint therewith. The valve cis preferably faced with a leather disk d, which, when the Valve isactuated by the spring g, will form a gastight joint on the circularridge 1". The gas passes into and out of the casing a through the pipesf f.

For the purpose of making a gas-tight joint where the valve stem passesthrough the cap b, there is provided astufting-box 6, containingsuitable packing, and which is pressed against a central hub upon theinner side of the cap b by the spring g. The spring thus performs thedouble office of keeping the stuffing-box gas-tight and impelling thevalve 0 against its seat.

To the valve stem 0 is jointed the lever 71, the hooked end of whichengages in the threads of a left-handed screw m, fastened to the end ofthe center arbor of the clock movement contained in the case p. The

screw m should have as many, or more threads in number as the number ofhours during which it is desired that the flow of gas off by thecontinued revolutions of the clock arbor, and finally suddenly released.It will be observed that the movement of the lever along the threads ofthe screw will be in a' plane at a right angle to the center line of thevalve stem 0, and the latter will be turned thereby. To provide for thismovement, the fulcrum of the lever h is on a circular ridge n, upon theface of the cap b. The lever is thus allowed to accommodate itselfwithout cramping itself or the valve stem.

As a matter of convenience, the screw m is so fastened upon the clockarbor that it will cast off the lever h when the minute hand reaches thefigure XII. I

In Fig. 2, is shown an alternative construction of the valve, in which astuffing-box is dispensed with.' The valve stem 0 passes through thecenter of a flexible diaphragm is, the periphery of which is secured andrendered gas-tight by the thimble i, which forms a continuation of thethreaded part of the cap 1). The conical spiral spring Z? bears againstthe diaphragm at its center, and.

serves the double purpose of preventing leakage at this point andclosing the valve.

When it is desired to operate the device, the clock is wound and set inmotion,'and the lever h is brought down and engaged with a screw threadon the casting-off screw m. If it is desired to continue the operationof the device for a fractional part of an hour, the minute hand of theclock is set to the desired number of minutes, counting backward fromthe figure XII, and the lever is engaged with the thread nearest thefree end of the screw. For each additional hour, it is moved along onethread. The continued revolution of the clock arbor will finally castoff the lever from the free end of the screw, when the spring willclosethe valve. The apparatus is thus capable of adjustment for any timefrom a minute to as many hours as there are threads upon the casting-offscrew, and the desired time can be easily gaged to within a few seconds.It is evident that other means than those specified herein can beemployed for keeping the valve stem 0 gas-tight where it passes outthrough the casing. I have shown two ways for accomplishing it, but I donot confine myself to either; for other means, well known to mechanics,may be employed without departing from the spirit of my invention.

I therefore claim- 1. In a device fortiming the flow of gas, thecombination of a spring seated valve, a clock movement, provided with arotating casting 0h. screw, and a lever, having one end connected to thevalve stem, and operating to lift the valve from its seat, and its otherend adapted for engagement with the casting ofi screw; said lever havingits fulcrum at one end of the valve casing, substantially ashereinbefore set forth.

2. In a device for timing the flow of gas, the combination of a clockmovement provided with a rotating casting ofl": screw, a recipr0 eatingvalve provided with a stem, a lever having one end connected to thevalve stem, and its other end adapted for engagement with the castingoff screw to unseat the valve, a stuffing box surrounding the valvestem, and a spring situated between the valve and stufling box, andadapted to compress the packing in the stufiing box and to seat thevalve when the lever is released; substantially as hereinbefore setforth.

3. In a device for timing the flow of gas, the combination of the valvecasing a, having an opening surrounded by a circular ridge 'n, thereciprocating spring seated valve 0, having its stem extended throughthe said opening, a clock movement, provided with a rotating casting ofiscrew m, and the lever h, fulcrumed on the circular ridge n, and havingone end connected with the valve stem, and its other end adapted forengagement with the casting 40 off screw; substantially as hereinbeforeset forth.

GEORGE E. SNOW. Witnesses:

EDWIN R. DAVIS, O. E. DAVIS.

